CN1327233C - Measuring circuit of electric rheological liquid high electric field strength dielectric constant - Google Patents
Measuring circuit of electric rheological liquid high electric field strength dielectric constant Download PDFInfo
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- CN1327233C CN1327233C CNB2005100284606A CN200510028460A CN1327233C CN 1327233 C CN1327233 C CN 1327233C CN B2005100284606 A CNB2005100284606 A CN B2005100284606A CN 200510028460 A CN200510028460 A CN 200510028460A CN 1327233 C CN1327233 C CN 1327233C
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Abstract
The present invention relates to a measuring circuit of electric rheological fluid high electric field strength dielectric constant, which belongs to the field of measuring systems and comprises a signal input terminal, a phase reverser, a light-emitting diode, a resistor, four switching diodes, two bootstrap capacitors, a high-voltage isolation driving chip IR2130, four high-voltage switching MOSFET tubes IRFPC50, a measured capacitor, a buffer capacitor, an integrating capacitor, a feedback resistor, an operational amplifier and a measured result voltage value output terminal. The present invention uses the 600 V high-voltage resistant high-voltage isolation driving chip IR2130 with a suspended bootstrap power supply, the 600V high-voltage resistant switching MOSFET tubes, and the four ultra-fast return switching diodes which can resist 700V high voltage to ensure that the measuring circuit reliably works under 500V charging voltage. The measuring accuracy of the present invention is not influenced by a parasitic capacitor, and the present invention can measure the dielectric constant of the electric rheological fluid under the condition of high electric-field intensity.
Description
Technical field
What the present invention relates to is a kind of circuit of field of measuring technique, a kind of specifically measuring circuit of electric rheological liquid high electric field strength dielectric constant.
Background technology
Electrorheological fluid is a kind of SMART FLUID material.Under electric field action, it is solid-state that it can change class into by liquid state moment; After electric field was cancelled, it again can be promptly from the solid-state liquid state that returns to of class.Up to the present, the required electric field intensity of electrorheological fluid generation significant rheology effect is generally all more than 2000V/mm.Specific inductive capacity is one of important parameter of electrorheological fluid research.Generally be full of the electric capacity of the plates capacitance of electrorheological fluid, calculate the specific inductive capacity of electrorheological fluid then by measurement.Existing capacitance measurement method is divided three classes: succusion, impedance measurement (comprising various bridge measurement technology) and charge and discharge electrical method.In actual applications, electrorheological fluid always is subjected to the open and close formula effect of a unidirectional electric field, and the measuring method similar with this mode of operation is to charge and discharge electrical method.The general measuring accuracy that charges and discharge electrical method is subjected to the influence of stray capacitance easily.On the other hand, owing to be subjected to the restriction of metering circuit power supply and device withstand voltage, in all these metering circuits or device, the charging voltage value of measured capacitance all lower (＜30V), distance with two pole plates of electric capacity is that 0.25mm calculates, electric field intensity amplitude between capacitor plate is less than 120V/mm, far below electrorheological fluid take place the required electric field intensity of remarkable effect (＞2000V/mm).
Find through literature search prior art, China Patent No.: 01112515.2, denomination of invention: capacitive chromatographic imaging capacitance measuring system, this patent have adopted a charge amplifier, two sampling holders and the capacitance measurement circuit that instrumentation amplifier is formed.Driving voltage switches variation and the transfer that causes the quantity of electric charge on the measured capacitance between two level, two the stable state output voltages of charge amplifier before and after driving voltage changes are sampled by two sampling holders respectively and kept.The output voltage of two sampling holders is input to the positive and the inverting input of instrumentation amplifier respectively, then dc voltage value that is directly proportional with the measured capacitance amount of instrumentation amplifier output.Can calculate the capacitance of measured capacitance device according to the output voltage values of the electric capacity of feedback capacity on two level difference values of excitation voltage source, the charge amplifier and instrumentation amplifier.This circuit has been avoided the influence of stray capacitance to measurement result on principle.If the voltage of driving source in the circuit is increased to high pressure about 500V, then has two possibilities that cause circuit to damage.If the measured capacitance device punctures, the voltage of driving source can directly be added to the inverting input of charge amplifier so, thereby damages charge amplifier.Another possibility occurs in driving source and turns on and off constantly, and when driving source was opened, the voltage at measured capacitance two ends was zero, at this moment will have+voltage of 500V is added to the inverting input of charge amplifier, and charge amplifier will be damaged; When driving source turn-offed, its output voltage was zero, and the voltage of the inverting input of charge amplifier equals-500V, can cause charge amplifier to be damaged equally.Therefore, this circuit can not be used for measuring the specific inductive capacity of electrorheological fluid under high electric field intensity condition.
Summary of the invention
The present invention is directed to the deficiencies in the prior art and defective, a kind of measuring circuit of electric rheological liquid high electric field strength dielectric constant is provided, make it, realize the measurement of electrorheological fluid specific inductive capacity under the high electric field intensity condition based on high voltage capacitor charge and discharge principle.
The present invention is achieved by the following technical solutions, comprising: signal input terminal, phase inverter, light emitting diode, resistance, four switching diodes, two bootstrap capacitors, high pressure isolation drive chip I R2130, four high-voltage switch gear MOSFET manage IRFPC50, measured capacitance, buffer capacitor, integrating capacitor, feedback resistance, operational amplifier, measurement result voltage lead-out terminal.Circuit connecting relation is: signal input terminal is divided into two-way, and one the road is directly inputted to HIN2 pin and the LIN2 pin on the IR2130; Another road signal is received the input end of phase inverter, and the output terminal of phase inverter is received HIN1 pin and the LIN1 pin on the IR2130; The power supply of circuit has two-way, and one the tunnel is+15V, and another road is+500V that the two-way power supply altogether; + 15V power supply and ground wire are received the power supply input pin and the ground wire pin of phase inverter, IR2130 and operational amplifier respectively; The positive pole of light emitting diode is received+the 15V power supply, and negative pole connects a current-limiting resistance, and this resistance is received the FAULT pin of IR2130 again; The positive pole of first switching diode is connected to+the 15V power supply, and negative pole is connected to the VB1 pin of IR2130; The positive pole of second switching diode is connected to+the 15V power supply, and negative pole is connected to the VB2 pin of IR2130; A pin of first bootstrap capacitor is connected to the VB1 pin of IR2130, and another pin is connected to the VS1 pin of IR2130; A pin of second bootstrap capacitor is connected to the VB2 pin of IR2130, and another pin is connected to the VS2 pin of IR2130; The pin HO1 of IR2130 is connected to the gate pole of first IRFPC50 MOSFET power tube, and pin VS1 is connected to the source electrode of first IRFPC50 MOSFET power tube; The pin LO1 of IR2130 is connected to the gate pole of second IRFPC50MOSFET power tube; Pin VSO and the VSS of IR2130 are connected to ground wire; The pin HO2 of IR2130 is connected to the gate pole of the 3rd IRFPC50 MOSFET power tube, and pin VS2 is connected to the source electrode of the 3rd IRFPC50 MOSFET power tube; The pin LO2 of IR2130 is connected to the gate pole of the 4th IRFPC50MOSFET power tube; The drain electrode of first IRFPC50 MOSFET power tube is connected to+the 500V power supply; Source electrode is connected to the drain electrode of the 4th IRFPC50 MOSFET power tube, and the source electrode of the 4th IRFPC50MOSFET power tube is connected to ground wire; The positive pole of the 3rd switching diode is connected to the inverting input of operational amplifier, and negative pole is connected to the drain electrode of the 3rd IRFPC50 MOSFET power tube; The source electrode of the 3rd IRFPC50 MOSFET power tube is connected to the positive pole of the 4th switching diode, and the negative pole of the 4th switching diode is connected to the drain electrode of second IRFPC50 MOSFET power tube; The source electrode of second IRFPC50MOSFET power tube is connected to ground wire; A pole plate of measured capacitance is connected to the source electrode of first IRFPC50MOSFET power tube, and another pole plate is connected to the source electrode of the 3rd IRFPC50 MOSFET power tube; A pin of buffer capacitor is connected to the inverting input of operational amplifier, and the another pin is connected to ground wire; The normal phase input end of operational amplifier is connected to ground wire; A pin of integrating capacitor is connected to the inverting input of operational amplifier, and the another pin is connected to the output terminal of operational amplifier; Pin of feedback resistance is connected to the inverting input of operational amplifier, and the another pin is connected to the output terminal of operational amplifier; The output terminal of operational amplifier is connected to measurement result voltage lead-out terminal.
Therefore the present invention has fundamentally eliminated the influence of stray capacitance to measuring accuracy owing to having adopted the switching capacity based on the charge transfer principle to measure basic circuit.Adopt the 500V high pressure that measured capacitance is charged, correspondingly, adopt the high pressure of anti-600V and have the Switching Power Supply special driving chip IR2130 of suspension bootstrap power supply and switch mosfet pipe that can the high pressure of anti-600V, and the Ultrafast recovery switching diode of four high pressure of anti-700V therein, guarantee that metering circuit works reliably under the 500V charging voltage.The present invention can effectively avoid the influence of stray capacitance to measurement result.Measure the electric capacity under the different capacitor plate distance conditions and calculate corresponding electrorheological fluid specific inductive capacity, analyze the relation between dielectric constant measurement result and the electric field intensity then, can obtain the detailed characteristics of electrorheological fluid specific inductive capacity under the high electric field intensity condition, help more comprehensively and in depth to disclose the relation between electric rheological effect and the specific inductive capacity.
Description of drawings
Fig. 1 metering circuit figure of the present invention
Embodiment
As shown in Figure 1, the present invention includes: signal input terminal 1, phase inverter 2, light emitting diode 3, resistance 4, switching diode 5 and 6, bootstrap capacitor 7 and 8, high pressure isolation drive chip 9, high-voltage switch gear MOSFET pipe 10,11,12 and 15, switching diode 13 and 14, measured capacitance 16, buffer capacitor 17, integrating capacitor 18, feedback resistance 19, operational amplifier 20, measurement result voltage lead-out terminal 21.
The pin HO1 of high pressure isolation drive chip 9 is connected to the gate pole of high-voltage switch gear MOSFET pipe 10, and pin VS1 is connected to the source electrode of high-voltage switch gear MOSFET pipe 10; The pin LO1 of high pressure isolation drive chip 9 is connected to the gate pole of high-voltage switch gear MOSFET pipe 15; The pin VSO and the VSS of high pressure isolation drive chip 9 are connected to ground wire; The pin HO2 of high pressure isolation drive chip 9 is connected to the gate pole of high-voltage switch gear MOSFET pipe 12, and pin VS2 is connected to the source electrode of high-voltage switch gear MOSFET pipe 12; The pin LO2 of high pressure isolation drive chip 9 is connected to the gate pole of high-voltage switch gear MOSFET pipe 11.
When the present invention worked, square-wave signal was divided into two-way behind signal input terminal 1 place in circuit, and one the road is directly inputted to HIN2 and the LIN2 pin on the high pressure isolation drive chip 9, chip 9 with this signal condition after the break-make of control high-voltage switch gear MOSFET pipe 11 and 12; Another road signal is input to HIN1 and the LIN1 pin on the high pressure isolation drive chip 9 after phase inverter 2 is anti-phase, chip 9 with this signal condition after the break-make of control high-voltage switch gear MOSFET pipe 10 and 15.When chip breaks down, light emitting diode 3 is lighted, and resistance 4 plays the effect of electric current in the restriction light emitting diode 3.Switching diode 5 and bootstrap capacitor 7 constitute the suspension bootstrap power supply, for driving the relevant circuit supply of high-voltage switch gear MOSFET pipe 10 in the chip 9; Similarly, switching diode 6 and bootstrap capacitor 8 also constitute the suspension bootstrap power supply, for driving the relevant circuit supply of high-voltage switch gear MOSFET pipe 12 in the chip 9.The capacitor that two measuring pads and electrorheological fluid therebetween constitute is measured capacitance 16 (Cx). Switching diode 13 and 14 plays the effect of blocking-up high-voltage switch gear MOSFET pipe 12 and 15 endobiosis diode function separately respectively.The electric capacity of buffer capacitor 17 plays the effect of shifting and storing electric charge on the measured capacitance 16 much larger than the electric capacity of measured capacitance, has also suppressed the voltge surge of the inverting input of operational amplifier 20 simultaneously.The square wave driving signal of high-voltage switch gear MOSFET pipe 10 and 15 is anti-phase with the drive signal of high-voltage switch gear MOSFET pipe 12 and 11 on phase place.When high-voltage switch gear MOSFET pipe 10 and 15 was opened, measured capacitance was charged to 500V voltage.When high-voltage switch gear MOSFET pipe 12 and 11 was opened, the electric charge on the measured capacitance was transferred on the buffer capacitor 17.The charge amplifier that the total charge flow of charging constitutes through integrating capacitor 18, feedback resistance 19 and operational amplifier 20 in unit interval.Because the retroactive effect of charge amplifier, the charging total electrical charge in the unit interval produces the electric current on the feedback resistance 19 of flowing through.Integrating capacitor 18 plays integral action, the voltage at level and smooth feedback resistance 19 two ends.Metering circuit one of measurement result voltage lead-out terminal 21 output with charging voltage, discharge and recharge the DC voltage that frequency, feedback resistance value and measured capacitance amount are directly proportional.Charging voltage, discharge and recharge frequency and feedback resistance value is known, therefore can calculate the electric capacity of measured capacitance by measuring junction 21 output voltages.
Before the drain electrode of high-voltage switch gear MOSFET pipe 12 and 15, be connected in series switching diode 13 and 14 respectively, make high-voltage switch gear MOSFET pipe 12 and 15 separately the parasitic diode in the body lost efficacy, thereby high-voltage switch gear MOSFET pipe 12, switching diode 13 and high-voltage switch gear MOSFET pipe 15, switching diode 14 constitute two high-pressure electronic switches.
It is the Ultrafast recovery diode of 700V that switching diode 5,6,13 of the present invention and 14 adopts oppositely withstand voltage; The special driving chip IR2130 that high pressure isolation drive chip 9 adopts Int Rectifier Corp (International Rectifier Co.Ltd.) to produce, the highest withstand voltage 600V that reaches; High-voltage switch gear MOSFET pipe 10,11,12 and 15 adopts IR company to produce IRFPC50 MOSFET power tube, and withstand voltage is 600V; Make circuit under the effect of 500V charging voltage, still can work reliably.The charging voltage of setting electric capacity is 500V, if the spacing of capacitor plate is 0.5mm, electric field intensity is 1000V/mm so; If the spacing of capacitor plate is 0.25mm, electric field intensity is 2000V/mm so, and the like.Therefore keeping the charging voltage of electric capacity is 500V, just can regulate electric field intensity between the pole plate by the distance between the control capacittance pole plate.The present invention can effectively avoid the influence of stray capacitance to measurement result, obtains the detailed characteristics of electrorheological fluid specific inductive capacity under the high electric field intensity condition.
Claims (6)
1, a kind of measuring circuit of electric rheological liquid high electric field strength dielectric constant, comprise: signal input terminal (1), phase inverter (2), light emitting diode (3), resistance (4), bootstrap capacitor (7,8), measured capacitance (16), buffer capacitor (17), integrating capacitor (18), feedback resistance (19), operational amplifier (20), measurement result voltage lead-out terminal (21), it is characterized in that, also comprise: switching diode (5,6), high pressure isolation drive chip (9), high-voltage switch gear MOSFET pipe (10,11,12,15), switching diode (13,14), signal input terminal (1) is divided into two-way, one the road is directly inputted to HIN2 pin and the LIN2 pin on the high pressure isolation drive chip (9), another road signal is received the input end of phase inverter (2), and the output terminal of phase inverter (2) is received HIN1 pin and the LIN1 pin on the high pressure isolation drive chip (9); The power supply of circuit has two-way, one the tunnel is+15V, another road is+500V, the two-way power supply altogether, + 15V power supply and ground wire are received phase inverter (2) respectively, the power supply input pin of high pressure isolation drive chip (9) and operational amplifier (20) and ground wire pin, light emitting diode (3), switching diode (5,6) positive pole all is connected to+the 15V power supply, the negative pole of light emitting diode (3) connects resistance (4), resistance (4) is received the FAULT pin of high pressure isolation drive chip (9) again, switching diode (5,6) negative pole is connected respectively to the VB1 pin and the VB2 pin of high pressure isolation drive chip (9), a pin of bootstrap capacitor (7) is connected to the VB1 pin of high pressure isolation drive chip (9), and another pin is connected to the VS1 pin of high pressure isolation drive chip (9); A pin of bootstrap capacitor (8) is connected to the VB2 pin of high pressure isolation drive chip (9), another pin is connected to the VS2 pin of high pressure isolation drive chip (9), high pressure isolation drive chip (9) pin HO1 is connected to the gate pole of high-voltage switch gear MOSFET pipe (10), pin VS1 is connected to the source electrode of high-voltage switch gear MOSFET pipe (10), pin LO1 is connected to the gate pole of high-voltage switch gear MOSFET pipe (15), pin VSO and VSS are connected to ground wire, pin HO2 is connected to the gate pole of high-voltage switch gear MOSFET pipe (12), pin VS2 is connected to the source electrode of high-voltage switch gear MOSFET pipe (12), pin LO2 is connected to the gate pole of high-voltage switch gear MOSFET pipe (11), the drain electrode of high-voltage switch gear MOSFET pipe (10) is connected to+the 500V power supply, source electrode is connected to the drain electrode of high-voltage switch gear MOSFET pipe (11), the source electrode of high-voltage switch gear MOSFET pipe (11) is connected to ground wire, the positive pole of switching diode (13) is connected to the inverting input of operational amplifier (20), negative pole is connected to the drain electrode of high-voltage switch gear MOSFET pipe (12), the source electrode of high-voltage switch gear MOSFET pipe (12) is connected to the positive pole of switching diode (14), the negative pole of switching diode (14) is connected to the drain electrode of high-voltage switch gear MOSFET pipe (15), the source electrode of high-voltage switch gear MOSFET pipe (15) is connected to ground wire, a pole plate of measured capacitance (16) is connected to the source electrode of high-voltage switch gear MOSFET pipe (10), another pole plate is connected to the source electrode of high-voltage switch gear MOSFET pipe (12), a pin of buffer capacitor (17) is connected to the inverting input of operational amplifier (20), the another pin of buffer capacitor (17) is connected to ground wire, the normal phase input end of operational amplifier (20) is connected to ground wire, a pin of integrating capacitor (18) is connected to the inverting input of operational amplifier (20), the another pin is connected to the output terminal of operational amplifier (20), (19) pins of feedback resistance are connected to the inverting input of operational amplifier (20), the another pin is connected to the output terminal of operational amplifier (20), and the output terminal of operational amplifier (20) is connected to measurement result voltage lead-out terminal (21).
2, measuring circuit of electric rheological liquid high electric field strength dielectric constant according to claim 1 is characterized in that, described high pressure isolation drive chip (9), and maximum is withstand voltage to be 600V, and suspended power supply bootstrapping function is arranged.
3, measuring circuit of electric rheological liquid high electric field strength dielectric constant according to claim 1 is characterized in that, the charging voltage of described measured capacitance (16) is the 500V high pressure.
4, measuring circuit of electric rheological liquid high electric field strength dielectric constant according to claim 1 is characterized in that, described high-voltage switch gear MOSFET pipe (10,11,12,15), and maximum is withstand voltage to be 600V, the charging and the discharge of control measured capacitance (16).
5, according to claim 1 or 4 described measuring circuit of electric rheological liquid high electric field strength dielectric constant, it is characterized in that, described high-voltage switch gear MOSFET pipe (12,15), before its drain electrode, be connected in series switching diode (13,14) respectively, make high-voltage switch gear MOSFET pipe (12,15) the interior parasitic diode inefficacy of body separately, thereby high-voltage switch gear MOSFET pipe (12), switching diode (13) and high-voltage switch gear MOSFET manage (15), switching diode (14) constitutes two high-pressure electronic switches.
6, measuring circuit of electric rheological liquid high electric field strength dielectric constant according to claim 1 is characterized in that, described switching diode (5,6,13,14), and maximum is withstand voltage to be 700V.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100284606A CN1327233C (en) | 2005-08-04 | 2005-08-04 | Measuring circuit of electric rheological liquid high electric field strength dielectric constant |
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| Application Number | Priority Date | Filing Date | Title |
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| CNB2005100284606A CN1327233C (en) | 2005-08-04 | 2005-08-04 | Measuring circuit of electric rheological liquid high electric field strength dielectric constant |
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| CN1719265A CN1719265A (en) | 2006-01-11 |
| CN1327233C true CN1327233C (en) | 2007-07-18 |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2016044302A1 (en) | 2014-09-15 | 2016-03-24 | Bourns, Inc. | Conductive liquid property measurement using variable phase mixing |
| CN108828317A (en) * | 2018-04-18 | 2018-11-16 | 四川文理学院 | Electric resistance measuring apparatus and system |
| CN113271013B (en) * | 2021-05-13 | 2022-06-03 | 浪潮商用机器有限公司 | Buck chip drive circuit and Buck chip drive system |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5083089A (en) * | 1991-02-20 | 1992-01-21 | Spatial Dynamics, Ltd. | Fluid mixture ratio monitoring method and apparatus |
| US5519328A (en) * | 1994-10-28 | 1996-05-21 | Keithley Instruments, Inc. | Compensation for dielectric absorption effect |
| CN1482452A (en) * | 2003-06-13 | 2004-03-17 | 四川大学 | High sensitivity liquid dielectric constant measuring probe |
| CN1534303A (en) * | 2003-03-31 | 2004-10-06 | Tdk株式会社 | Method and apparatus for measuring complex dielectric constant of dielectric |
-
2005
- 2005-08-04 CN CNB2005100284606A patent/CN1327233C/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5083089A (en) * | 1991-02-20 | 1992-01-21 | Spatial Dynamics, Ltd. | Fluid mixture ratio monitoring method and apparatus |
| US5519328A (en) * | 1994-10-28 | 1996-05-21 | Keithley Instruments, Inc. | Compensation for dielectric absorption effect |
| CN1534303A (en) * | 2003-03-31 | 2004-10-06 | Tdk株式会社 | Method and apparatus for measuring complex dielectric constant of dielectric |
| CN1482452A (en) * | 2003-06-13 | 2004-03-17 | 四川大学 | High sensitivity liquid dielectric constant measuring probe |
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